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On China's Coal Use and Estimated CO2 Emissions Fell in 2014

It is great that Chinese CO2 emissions declined, but, as with most of these kinds of articles, it is important to point out that wind and solar played only a small part. In terms of electricity generated, the 2013-2014 increase from wind & solar combined is about 6 times smaller than that of hydro (estimated from this Chinese source). 2014 was a great year for Chinese hydro, but hydro is now nearing saturation (~20% of total generation). 

March 2, 2015    View Comment    

On The IEA's Central Projections for Renewables Continue to Look Way Too Low

This article neglects a very important point: a reduction in net additions does not mean a contraction in the industry. Especially for wind, the amount of capacity installations needed to replace old plants will increase sharply over coming years. In fact, as shown below, the IEA projects total yearly wind installations to almost double in the next 20 years. 

 

I agree that the IEA solar PV outlook in its central scenario is somewhat conservative. This outlook rests quite heavily on the assumption of a sharp contraction in Japan over the next few years (similar to what happened in Germany) and a gradual slowdown in China towards the 100 GW by 2020 government target.

50 GW of wind installations in 2014? This source says 33 GW. PV estimates are also pretty varied, strongly influenced by data regarding the year-end sprint in China.

It is also worthwhile to note that the thing that the IEA seems to be worst at predicting is coal (large underprediction). Please see my analysis of the past 15 years of IEA projections

March 2, 2015    View Comment    

On Seeking Consensus on the Internalized Costs of Bioenergy

Thanks for the comment. I corrected the biofuel cost graph by removing the oil reference on the x-axis. The aim here is simply to give the relationship between $/litre, $/gallon and $/barrel for easy comparison to other energy options at a later stage and conversion from the IEA graphs given at the top of the article. 

Regarding heating with wood, I only thought to include this to give some perspective since most people have no feeling for how much energy one GJ is. That being said though, your comment about including the capital costs of the wood burning stove is a valid one. Modern, highly efficient wood burning stoves can be quite expensive and, if the stove is not used much, the capital cost can be significant in the total levelized cost of heating.

However, if the stove is the primary heat source, an average family would consume about 2 cords per year. If this costs $500/year, the fuel costs will exceed the capital costs of the average stove after only 2 years or so, implying that capital costs are small relative to fuel costs over a 20-30 year lifetime. 

February 25, 2015    View Comment    

On Seeking Consensus on the Internalized Costs of Bioenergy

It is hard to know who to believe about biofuels, especially corn ethanol. Drawbacks like impacts on food supplies and low EROI are often mentioned, but the first graph in this article shows that production costs are quite reasonable. The corn price is also quite low despite significant ethanol production. 

I'm sure that we will have many more interesting discussions on this topic in future Seeking Consensus posts when we delve into matters such as externalized costs and total technical potential. 

February 23, 2015    View Comment    

On Seeking Consensus on the Internalized Costs of Bioenergy

DATA: Biofuel costs: $0.7/litre based on the IEA graphs above. 

February 23, 2015    View Comment    

On Seeking Consensus on the Internalized Costs of Bioenergy

DATA: Biomass LCOE: $101/MWh. This under the assumption that the average plant costs $2500/kW (average of developed and developing world), fuel costs of $7/GJ and all the other assumptions given in the article.

February 23, 2015    View Comment    

On Seeking Consensus on the Internalized Costs of Bioenergy

DATA: Raw biomass feedstock: $7/GJ. This is a rough estimate in the middle of the 3.5-10 $/GJ range given in the article. 

February 23, 2015    View Comment    

On Seeking Consensus on the Internalized Costs of Solar Thermal Energy

Fossil fuels are used directly for heat wherever it is practically possible (mostly industrial applications). Since electricity is manditory (or just much more practical) for many applications, we pay the thermodynamic penalty of generating electricity from fossil fuels.

Here I was just talking about water heating. Solar water heating is practical since it needs only very simple engineering and does not require any fuels going in or emissions going out of the system. Coal and nuclear would be totally impractical for this purpose, while natural gas is somewhat practical (thus achieving moderate deployment for water heating).

About your last paragraph, there is no need to worry. Future sections of this column will include articles on externalized costs and future internalized costs to give a complete and objective picture. 

 

February 14, 2015    View Comment    

On Comparing the Costs of Renewable and Conventional Energy Sources

The US is probably the best country in the world for the deployment of wind/solar energy due to the combination of a number of factors: 1) excellent wind/solar resources (wind and solar capacity factors are literally double the global average), 2) lots of space 3) stringent coal regulations greatly inflating capital costs, 4) abundant natural gas for balancing wind/solar and 5) good subsidy support. However, the figures presented in this article (Lazard) are over-optimistic, using low-end capital costs and high-end capacity factors. As shown below, real world numbers for wind and solar costs result in LCOE numbers which are 32% and 64% higher than Lazard's estimates respectively. 

Let's compare Lazard's 2012 analysis to real world data for wind and solar.

Wind:

Lazard: capital costs: $1500-2000, capacity factor: 30-48%

Real world: capital costs: $2000/kW average ($1400-4400/kW), capacity factor: 33% average (18-53%)

LCOE using 20 year lifetime, 6% discount rate and operating costs of $30/kW/yr:

Lazard $1750/kW and 39%: $53.4/MWh

Real world $2000/kW and 33%: $70.7/MWh (32% higher)

Solar:

Lazard: capital costs: $2000-2750/kW, capacity factor: 20-27%

Real world: capital costs: $4000/kW average ($2600-8000/kW), capacity factor 23% average (15-30%)

For PV it is important to distinguish between AC and DC capacity factors and costs, something which Lazard seems to have missed. 

LCOE using 30 year lifetime, 6% discount rate and operating costs of $30/kW/yr:

Lazard $2400/kW and 24%: $97.2/MWh

Real world $4000/kW and 23%: $159.1/MWh (64% higher)

February 14, 2015    View Comment    

On Seeking Consensus on the Internalized Costs of Solar Thermal Energy

DATA: Internalized cost of solar thermal water heating: $20/GJ. This is for a capital cost of $40/gal (e.g. $3200 for an 80 gallon system) and a solar fraction of 70% (fairly sunny location). 

February 12, 2015    View Comment    

On Seeking Consensus on the Internalized Costs of Solar Thermal Energy

DATA: Global average internalized cost of solar thermal electricity: $175/MWh. This is calculated at a capital cost of $7000/kW, a discount rate of 8% and a capacity factor of 45%.

February 12, 2015    View Comment    

On Report: Solar Added 50% More American Jobs than Oil and Gas Drilling and Pipeline Construction in 2014

Indeed. Statistics for the first nine months of 2014 found here shows that oil & gas added 3.005 quadrillion BTU while solar added only 0.096 - 31 times less. If solar actually added more jobs than oil & gas, it really speaks to enourmous economic inefficiency...

January 25, 2015    View Comment